Rotary heat exchangers, such as those produced and disclosed in U.S. Pat. No. 3,112,184, require costly and bulky accessory equipment such as ring gears, motors, rubbing seals and special housings to function effectively. The ceramic heat exchanger must also be quite strong and sealable to provide for the accessory equipment and the periodic rotation.
These problems of rotary heat exchangers can be solved by providing a fixed recuperator such as suggested by the copending U.S. patent application Ser. No. 660,879 of Everett Kelm which was filed of even date with this application and is assigned to the assignee of this application. Therein it is suggested that a honeycombed body may be modified by providing entrances and exits for a first fluid into selected cells through surfaces perpendicular to the entrance and exit openings in unselected cells for a second fluid so that first and second fluids may be separately applied to and passed through the honeycombed body. The modification requires that selected columns of cells are provided with the alternate entrances and exits and are then sealed at the original entrance and exit ends. The present invention relates to an improved method for providing alternate entrances and exits to selected columns of cells and for sealing the original open-ends of the cells in selected columns.